Ball-up detector



Jan. 3, 1939. J. E. McG OWA N 2,142,521

BALI -UP DETECTOR Filed June 10, 1937 2 Sheets-Sheet 2 JNVENTOR. Jlhn E.M 60 Wan A6652; MJ

' A TTORNE Y3 crumpled condition.

Patented Jan. 3, 1939 PATENT OFFICE BALL-UP DETECTOR John E. McGowan,Forest Hills, Long Island, N. Y., assignor to Miller Printing MachineryCompany, Pittsburgh, Pa.

Application June 10, 1937, Serial No. 147,414

8 Claims.

My invention pertains to devices for use in connection with machines,such as printing presses, to which sheets are fed one by one, fordetecting the feeding of a sheet which'is in a Such devices are commonlyknown in the printing trade as ball-up detectors.

When a sheet is fed in a crumpled condition to a machine for operatingthereon various harmful results are liable to follow. As one example ofthis in a cylinder printing press the crumpled sheet would present agreater than normal thickness of paper between the impression cylinderand the printing type or plates. Since a maximum pressure between thecylinder and the type, to give the required printing impression, mayalready obtain, the interposition of the extra thickness is likely todamage, or, batter the type or plates. Various automatic devices haveheretofore been proposed for the purpose of avoiding such difficultiesas this'by throwing the impression cylinder out of printing positionwith respect to the type, or, more usually, stopping the press whenevera crumpled sheet is fed forward for being seized by the grippers of theprinting cylinder.

It is the principal object of my invention to provide a detector devicefor this purpose which will be especially simple of construction andreliable in its operation.

Another object is to provide such a detector device which will work inconjunction with a device for detecting failures to feed a sheet, sothat the instrumentalities for actually throwing out the impression ofthe press, or stopping the press, are available for both detectordevices.

The detector device embodying my invention is shown, by way of example,in the accompanying drawings, and described in the followingspecification; but I wish it understood that the invention may beembodied in other forms and changes made in the particular formdescribed and shown without exceeding the scope thereof as defined inthe appended claims.

In the drawings:

Fig. 1 is a plan showing a portion of a frame, feed table, and one ofthe front drop-guides of a cylinder printing press, the drop-guidehaving associated therewith a detector device made in accordance with myinvention;

Fig. 2 is a side elevation of the same, th press frame being omitted andthe impression cylinder shown in section;

Fig. 3 is an enlarged plan of one of the dropguides;

Fig. 4 is a side view of the same, partly in section; and

Figs. 5 and 6 are front views showing the gauge plate of one of thedrop-guides, with the two detecting members carried thereby, Fig. 5showing the detecting member for crumpled sheets in its inoperativeposition and Fig. 6 showing this detecting member in its operativeposition.

The press indicated in the drawings includes a frame It] in which isrotatably supported, in the usual manner, a cylinder H, and with whichis associated a feed table l2 upon which the blank sheets are fed,either by hand or automatically, into a. position in which they arecorrectly placed for being drawn away by grippers on the cylinder l Atthe front end of the feed table, is a lip plate I3, the leading edge ofwhich comes close to the cylinder; and beneath the feed table is mounteda guide bar l4 upon which are supported a pair of tongues I5 of whichonly one is shown, these tongues being adjustable'laterally of the feedtable. The front ends of the tongues |5 extend beyond the lip plate l3and come into close proximity with the cylinder surface.

In suitable members such as that indicated at I6 is mounted a cross barI1 upon which are secured a pair of front drop-guides l8, one onlyofwhich is shown. Each front guide consists of a casting l9 having atubular portion 2|] in which is slidably mounted a stem 2|, a spring 22being interposed between the stem and the casting, and tending to pressthe stem 2| outwardly. Passing longitudinally through the casting l9 andthreaded into the stem 2| is a screw 23 having at its outer end aknurled head 24 with which engages a detent spring 25 mounted on top ofthe casting. To the front end of the stem 2| is secured a gauge plate 26having ears 2! extending downwardly therefrom and spaced apart adistance something greater than the width of the associated tongue I 5,so that when the gauge plate rests upon the tongue the ears will extenddownwardly on each side of the latter, as shown in Figs. 5 and 6,thereby preventing the edge of the sheet from entering beneath-the gaugeplate. 'A fine adjustment of the gauge plate towards and from the feedtable can be effected by rotating the knurled head 24 manually, suchhead being retained in its adjusted position by means of the detentspring 25. By manipulating the knurled heads 24 of the two front guides,and by adjusting a side register device on the feed table (of which manykinds are well known in the art), the position of the sheet on thecylinder can be determined with great accuracy. The sheet is, of course,fed against the gauge plates 26 of the front guides, so that its frontedge is exposed, except for those portions which lie on the tongues I5.From this position it is withdrawn by the grippers on the cylinder II,the front guides being made to rise, in a. well known manner, to permitthis.

For detecting the presence or absence of a sheet at the gauge plates 26of the front guides, each gauge plate has pivoted thereto a detectingmember 28, which includes a pair of arms 29 connected by a pin 30 whichis pivotally mounted in ears 3| extending rearwardly from the gaugeplate. The arms 29 are connected by a front portion 32 having adownwardly extending leaf 33 and an upwardly extending leaf 34. Thedownwardly extending leaf 33 is adapted to enter a slot 35 formed in theassociated tongue I5, and the arms 29 are provided with a counterweight36 which tends to swing the whole detecting member 28 into a position inwhich the leaf 33 stands in the slot 35 in a position in advance of thegauge plate 26, as indicated in Fig. 4.

The stem 2| is made hollow and contains a plunger 31 which is normallypressed outwardly by means of a spring 38 disposed between said plungerand the end of the screw 23, the possible outward movement of theplunger being limited by a screw 39. The plunger protrudes from thefront end of the stem 2| and is formed at that point with a head 40having an annular groove 4| formed therein. The position and dimensionsof the parts are such that when the detector member is in its normalposition, shown in Fig. 4, its upper leaf 34 will be disposed in thegroove 4|, and will prevent movement of the plunger inwardly withrespect to the stem 2|. When, however, a sheet is fed correctly, so thatits edge comes into registering engagement with the gauge plate 26, suchedge will push the lower leaf 33 forward, rocking the detector memberabout its pivot, and cause such lower leaf to enter a slot 42 formed forthe purpose in the gauge plate 26. Such rocking movement of the detectormember will cause its upper leaf 34 to swing forward into a position inwhich it no longer enters the groove 4| of the plunger 31. In thesecircumstances, the plunger 31 is free to move inwardly with respect tothe sleeve 2|. It is the fact of whether or not the plunger 31 is freefor inward movement that controls whether the press shall continue toprint, or whether it shall be stopped, or its impression shall be thrownoff.

Extending across the feed table I2 is a rock shaft 43 operated upon by atorsion spring 44, or some other means tending to rock the same in aclockwise direction, when viewed as in Fig. 2. Such rock shaft hasmounted for lateral adjustment thereon a pair of tappet levers 45, onefor each of the front drop guides. These tappet levers have engagingportions 46 which, when the parts are adjusted, stand opposite the heads40 of the plungers 31. At its outer end, the shaft 43 is provided with alever 41 having an abutment portion 48 which lies above a verticallyreciprocable rod 49. The details of the mechanism actuating, andactuated by, the rod 49 are not of interest here. The rod isreciprocated once for each cycle of the press, thereby, by itsengagement with the abutment portion 48, cansing the shaft 43 to rockagainst the action of its spring 44, and then return. The mechanism,further, is such that when, at a time when a sheet should be presentedto the front guides, the spring 44 does not, through the lever 41, exertits pressure downwardly upon the rod 49, the press will either bestopped, or the impression of the press will be thrown off, or both,according to how it is desired to constitute the mechanism. Usually thepress will be stopped. When, however, at that period, pressure of thespring 44 is exerted downwardly on the rod 49, the press will continueto print.

When the sheets are fed correctly, so as to make registering engagementwith the gauge plates 26 of the front guides, the detecting members 28will be pushed forward so that their upper leaves 34 pass out of theslots 4| of the plungers 31. Under these conditions, when the rod 49descends, the engaging portions 46 of the tappet levers 45 can push theplungers inwardly with respect to the stems 2|, and accordingly theshaft 43 can rock clockwise under the action of its spring 44, thelatter exerting a downward thrust upon the rod 49. Under theseconditions, the press will continue to print. When, however, a sheetdoes not reach the gauge plates 26 of the front guides, the detectormembers 28 will remain in the position shown in Fig. 4, in which theupper leaves 34 lie in the grooves 4| of the plungers 31. In thesecircumstances, when the rod 49 descends and the spring 44 causes theengaging portions 46 of the tappet levers 45 to push against the heads40 of the plungers 31, the latter are prevented, by the upper leaves 34,from moving inwardly, and the shaft 43 is thereby held against furtherrocking movement. Thus the spring 44 cannot exert any downward pressureupon the rod 49. Under these conditions, the press will either bestopped, or its impression will be thrown off, or both, according to howthe mechanism isconstituted. There are two of the front guides andassociated detecting members, either of which functions separately.Therefore if a sheet should be fed properly against the gauge plate 26of one front guide, but not against the other, the press stoppage, orimpression throw off, or both, will occur, as will also take place if asheet having a portion of its front edge torn away should presentitself.

The detecting member 28, the operation of which has just been described,functions whenever a sheet is not fed to the drop-guides or when a sheethaving a torn front edge is fed. A crumpled sheet would be fed into thepress, which would continue running in the ordinary manner, providingthat portions of such crumpled sheet reached and moved both of thedetecting members 28. To prevent this I provide, upon the gauge plate 26of each drop-guide, a second detecting member, 50, such member beingpivoted, at 5| (Figs. 5 and 6) to the gauge plate to one side of thevertical center thereof. At the other side of the center of the gaugeplate the detecting member is provided with a downwardly extending leg52 formed with a forwardly extending foot 53 which is disposed parallelwith the adjacent tongue I5 and terminates in an upwardly inclinedportion 54. Extending upwardly from the detecting member is an arm 55having a lateral lug 56 disposed opposite the annular recess 4| of theplunger-head 40. As will be seen, the foot 53 of the detecting membernormally rests upon the tongue I 5, and the parts are so constructed andpositioned that, in these circumstances, the lug 56 is out of the recess4| of the plunger-head 40. However, if a sheet crumpled at or near itsfront edge (the most usual place where crumpling is encountered) shouldbe fed so as to reach the .gauge plates of the drop guides the crumpledportion of such sheet, in entering beneath the foot 53 of the detectingmember 50, will cause such member to tilt upwardly about its pivot 5iinto the position shown in Fig. 6, in which the lug 58 would enter therecess 4| of the plunger-head, preventing inward movement of theplunger, in the manner that has been described above, with respect tothe leaf 34 of the detecting member 28 and causing either the impressionof the press to be thrown off or the press to be stopped, or both.

It will immediately be appreciated that the invention is characterizedby an important advantage over prior devices which are effective to stopthe press only in case of failure to feed a sheet or in case of thefeeding of a sheet with a torn edge. The invention provides theadditional safeguard against the feeding of crumpled sheets which isjust as undesirable as the operation of the press in the absence of asheet or with a torn sheet.

Although I have illustrated and described herein but a preferredembodiment of the invention, changes in the construction and operationdisclosed may be made without departing from the spirit of the inventionor the scope of the appended claims.

I claim:

l. The combination with a printing-press sheet feed includingperiodically operating means preventing a stoppage of the press, aretractible plunger, means operating with said first men tioned meansfor retracting said plunger, and means actuated to inoperative positionby the feeding of a sheet, normally preventing retraction of saidplunger, of means normally inefiective but operable by the feeding of abailed-up sheet into position to prevent retraction of said plunger.

2. The combination with a printing-press sheet feed, of means effective,unless operated on each cycle of the press, to suspend operation of thepress, a retractible plunger, means actuated on operation of said firstmentioned means to retract the plunger, and a detector movably mountedadjacent said plunger and operable into a position preventing retractionof the plunger, on feeding of a balled-up sheet.

3. The combination with a printing-press sheet feed, of means effective,unless operated on each cycle of the press, to suspend operation of thepress, a retractible plunger, means actuated on operation of said firstmentioned means to retract the plunger, and a detector pivoted adjacentsaid plunger and movable into a position preventing retraction of theplunger, by the feeding of a balled-up sheet.

4. The combination with a printing-press sheet feed, of means effective,unless operated on each cycle of the press, to suspend operation of thepress, a retractible plunger, means actuated on operation of said firstmentioned means to retract the plunger, and a detector movably mountedadjacent said plunger and operable into a position preventing retractionof the plunger, said detector having a foot adapted to be engaged by acrumpled sheet.

5. The combination with a printing-press sheet feed, of means effective,unless operated on each cycle of the press, to suspend operation of thepress, a retractible plunger, means actuated on operation of said firstmentioned means to retract the plunger, and a detector movably mountedadjacent said plunger, said detector comprising a lever pivoted abovethe path of travel of the sheet on an axis substantially parallelthereto, and having an upturned foot whereby it is operated into aposition preventing retraction of said plunger, by the feeding of acrumpled sheet.

6. In a printing press, the combination with means normally operatedperiodically to prevent suspension of operation of the press, and meansoperated therewith for retracting a yieldable plunger, of a leverpivoted adjacent said plunger, normally preventing retraction thereof,but tilted to ineffective position by arrival of a sheet, and a secondlever adjacent said plunger and normally ineffective but tilted to aposition in which it looks said plunger against retraction, by thearrival of a crumpled sheet.

'7. A ball-up detector for the sheet-feed of a printing press, havingmeans normally operated periodically to prevent suspension of operationof the press including a yieldable plunger and means for retracting it,said detector comprising a lever pivoted below said plunger, said leverhaving a portion adapted to be engaged and displaced by a crumpled sheetand a portion adapted to be moved thereby into position to lock saidplunger against retraction.

8. In a sheet feed, for a printing press, a gauge for arresting a sheet,a lever pivoted thereadjacent so as to be actuated by a sheet advancedto said gauge, a plunger reciprocably mounted adjacent said lever, saidlever having a portion normally preventing retraction of said plunger, asecond lever pivoted adjacent said gauge and having a portion effectiveon tilting of the lever to prevent retraction of said plunger, and meanson said second lever adapted to be engaged by a crumpled sheetapproaching said gauge whereby to tilt the second lever.

JOHN E. MCGOWAN.

